Konstruktionsutveckling av Garfieldlucka

Sammanfattning: In the converter hall at Rönnskärsverken in Skelleftehamn, there are three Pierce-Smith converters forthe manufacturing of copper. Associated with each converter is a converter hood whose purpose is todeal with the process gases that develop during the copper refining process. To this converter hood is ahatch called Garfield, whose purpose is to enable loading of material and tapping of the converterrespectively. This study involves a design development of this Garfield hatch. The problem with thecurrent design seems to be varied, but this study is limited and largely deals with the determination ofthe new placement of lift shackles and control of the strength of the door's framework is arbitrary forthe new placement. The existing structure is compared with the previous one to present what changeshave taken place to justify the upcoming changes to the developed structure. The location is desired tobe changed so that the door hangs parallel to the converter hood during assembly and disassembly. Thisis accomplished by determining the center of gravity of the Garfield hatch and moving the lifting centerof the shackle that attaches to the traverse crane. This so that the door as a system achieves torqueequilibrium when it hangs from the traverse crane so that the horizontal plane of the Garfield hatch isparallel to the angle of the converter hood. Once the position of the shackle is determined, both the beamto which the shackle is attached are simulated and the truss in which the shackle beam is included. Thisis to investigate whether stresses in the material that develops in the shackle beam is too high to accept.Since the calculation basis for the existing location of the shackle is lacking, simulation is performedfor both the existing and the revised version. Through this, one can investigate how the stresses differbetween the different designs. The result of this is that the position of the shackle can be moved to theposition where torque equilibrium is achieved, and the Garfield hatch hangs parallel to the converterhood and the developed stresses are within acceptable levels for the material.In addition to the position of the shackle, it is also being investigated whether a solution can beimplemented to facilitate the orientation of the Garfield hatch during assembly. The solution to this isthe mounting of loops on the sides of the frame assembly to which control straps can be attached toobtain a rotation of the Garfield hatch under the lift. The loops are heavily oversized but should not beused to attempt to lift the Garfield hatch in any way.The design solution of the Garfield hatch cassette modules which constitute the abdomen of the hatchunder the framework and the sealing layer is evaluated. In terms of these, they can be replaced by asolution that can obtain a more reliable service life as they tend to lose their function relatively quicklydue to the harsh environment in the converter hood.The result shows that the revised position of the shackle obtains the desired angle and meets therequirements for strength.